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Файл:Физика (Physics). Английский язык. Тексты для чтения, перевода и обсуждения. Учебно-методическое пособие
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laws that conformed with a modified heliocentric theory. Galileo, having heard
of the invention of the telescope, constructed one of his own and, starting in
1609, was able to confirm the heliocentric system by observing the phases of
the planet Venus. He also discovered the surface irregularities of the moon, the
four brightest satellites of Jupiter, sunspots, and many stars in the Milky Way.
Galileo's interests were not limited to astronomy; by using inclined planes and
an improved water clock, he had earlier demonstrated that bodies of different
weight fall at the same rate (thus overturning Aristotle's dictums), and that
their speed increases uniformly with the time of fall. Galileo's astronomical
discoveries and his work in mechanics foreshadowed the work of the 17thcentury English mathematician and physicist Sir Isaac Newton, one of the
greatest scientists who ever lived.
usher ['ʌʃR] 1. 1) швейцар; билетёр 2) вестник, предвестник 2. провожать, сопровождать; вводить
the theory he ushered into the world — теория, которую он представил миру
usher in возвещать (наступление, приход чего-л.)
When was the atomic age ushered in? — Когда началась ядерная эпоха?
propound [prR'paund] 1) предлагать на обсуждение 2) выставить (аргумент) ;
выступить с предложением, предложить.
convince [kRn'vɪn(t)s] 1) убеждать (сделать что-л), уверять (в чём-л.) , доводить
до чьего-л. сознания
I'm convinced (that) she's lying. — Я убеждён, что она лжёт.
We were able to convince the students of the need for wider reading. — Нам уда-
лось убедить студентов в необходимости привлекать больше литературы.
confirm [kRn'fɜːm] подтверждать, подкреплять
to confirm smb. in his decision — поддержать кого-л. в его решении
Please, confirm your message. — Подтвердите, пожалуйста, ваше сообщение.
The President confirmed that a conference would take place. — Президент под-
твердил, что конференция состоится.
enunciation [ɪˌnʌn(t)sɪ'eɪʃ(R)n] формулировка, изложение, извещение, опов е-
щение
general enunciation – общая формулировка
particular enunciation – частная формулировка
incline 1. ['ɪnklaɪn] наклонная плоскость; наклон, скат (обычно о дороге или
железнодорожном полотне) 2. [ɪn'klaɪn] а) наклоняться, склоняться, к лон ит ься б)
наклонять, склонять
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The news inclined me to leave at once. — Новости заставили меня сразу же
уехать.
foreshadow [fɔː'ʃædRu] предвещать, предзнаменовывать, п редрекать, предсказывать
NEWTON AND MECHANICS
Starting about 1665, at the age of 23, Newton enunciated the principles of
mechanics, formulated the law of universal gravitation, separated white light
into colors, proposed a theory for the propagation of light, and invented differential and integral calculus. Newton's contributions covered an enormous
range of natural phenomena: He was thus able to show that not only Kepler's
laws of planetary motion but also Galileo's discoveries of falling bodies follow
a combination of his own second law of motion and the law of gravitation, and
to predict the appearance of comets, explain the effect of the moon in producing the tides, and explain the precession of the equinoxes.
The Development of Mechanics
The subsequent development of physics owes much to Newton's laws of
motion, notably the second, which states that the force needed to accelerate an
object will be proportional to its mass times the acceleration. If the force and
the initial position and velocity of a body are given, subsequent positions and
velocities can be computed, although the force may vary with time or position;
in the latter case, Newton's calculus must be applied. This simple law contained another important aspect: Each body has an inherent property, its inertial mass, which influences its motion. The greater this mass, the slower the
change of velocity when a given force is impressed. Even today, the law retains its practical utility, as long as the body is not very small, not very massive, and not moving extremely rapidly. Newton's third law, expressed simply
as “for every action there is an equal and opposite reaction,” recognizes, in
more sophisticated modern terms, that all forces between particles come in
oppositely directed pairs, although not necessarily along the line joining the
particles.
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propagation [ˌprɔpR'geɪʃ(R)n] 1) воспроизведение, размножение 2) распространение (идей и т.п.)
propagation of light – распространение света
contribution [ˌkɔntrɪ'bjuːʃ(R)n] 1) пожертвование, взнос 2) налог; контрибуция
3) вклад, ценные достижения
She made an outstanding contribution to science. — Она внесла огромный вклад
в науку.
The smallest contribution will be thankfully received. — Даже самые маленькие
взносы будут приняты с благодарностью.
enormous [ɪ'nɔːmRs] громадный; гигантский, обширный, огромный
an enormous fortune — несметное богатство
These avalanches consist of enormous blocks of ice. — Эти лавины состоят из
огромных кусков льда.
predict [prɪ'dɪkt] предсказывать, пророчить; прогнозировать
How often an observer can predict man's actions better than the man himself. —
Как часто наблюдатель может предсказать действия человека лучше, чем сам
человек.
subsequent ['sʌbsɪkwRnt] более поздний, последующи й, сл едующий
subsequent chapter — следующая глава
My subsequent destination was Vienna. — Моим следующим пунктом назначе-
ния была Вена.
The subsequent development of physics… – Последующее развитие физики…
notably ['nRutRblɪ] 1) исключи тель но , особенно, в особенности, боль ш е всего
2) весьма, заметно, очень, сильно
vary ['vɛRrɪ] 1) а) изменять , менять б) меняться, 2) разниться; отличаться, раз-
личаться, расходиться изменяться
to vary directly (inversely) — изменяться прямо (обратно) пропорционально
to vary with smth. — меняться в зависимости от чего-л.
to vary in smth. — расходиться в чём-л.
to vary in size — изменяться в размере
to vary considerably / greatly — сильно отличаться
Opinions vary on this point. — Мнения по этому вопросу расходятся.
They vary in their opinions. — У них разные точки зрения.
inherent [ɪn'her(R)nt] обязательно присущий, неотъ ем лем ы й
Some shortcomings were inherent in our approach. — Нашему подходу были
присущи определённые недостатки
sophisticated [sR'fɪstɪkeɪtɪd] 1) утончённый 2) искуш ён ны й , изощрённый 3)
умудрённый (опытом), опытный 4) а) сложный, сложно устроенный
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a sophisticated scholar — умудрённый опытом учёный
a sophisticated expert — опытный эксперт
one of the most sophisticated of animal communication systems — одна из самых
сложных систем коммуникации, используемых животными
Sophisticated search techniques would be required to locate faint objects. — Для
поиска слабо светящихся объектов потребуются (более) сложные методы.
Gravity
Newton's more specific contribution to the description of the forces in nature was the elucidation of the force of gravity. Today scientists know that in
addition to gravity only three other fundamental forces give rise to all observed
properties and activities in the universe: those of electromagnetism, the socalled strong nuclear interactions that bind together the neutrons and protons
within atomic nuclei, and the weak interactions between some of the elementary particles that account for the phenomenon of radioactivity. Understanding
of the force concept, however, dates from the universal law of gravitation,
which recognizes that all material particles, and the bodies that are composed
of them, have a property called gravitational mass. This property causes any
two particles to exert attractive forces on each other (along the line joining
them) that are directly proportional to the product of the masses, and inversely
proportional to the square of the distance between the particles. This force of
gravity governs the motion of the planets about the sun and the earth's own
gravitational field, and it may also be responsible for the possible gravitational
collapse, the final stage in the life cycle of stars..
One of the most important observations of physics is that the gravitational
mass of a body (which is the source of one of the forces existing between it
and another particle), is effectively the same as its inertial mass, the property
that determines the motional response to any force exerted on it. This equivalence, now confirmed experimentally to within one part in 1013, holds in the
sense of proportionality—that is, when one body has twice the gravitational
mass of another, it also has twice the inertial mass. Thus, Galileo's demonstrations, which antedate Newton's laws, that bodies fall to the ground with the
same acceleration and hence with the same motion, can be explained by the
fact that the gravitational mass of a body, which determines the forces exerted
15
on it, and the inertial mass, which determines the response to that force, cancel
out.
The full significance of this equivalence between gravitational and inertial
masses, however, was not appreciated until Albert Einstein, the theoretical
physicist who enunciated the theory of relativity, saw that it led to a further
implication: the inability to distinguish between a gravitational field and an
accelerated frame of reference
The force of gravity is the weakest of the four forces of nature when elementary particles are considered. The gravitational force between two protons,
for example, which are among the heaviest elementary particles, is at any given distance only 10
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the magnitude of the electrostatic forces between them,
and for two such protons in the nucleus of an atom, this force in turn is many
times smaller than the strong nuclear interaction. The dominance of gravity on
a macroscopic scale is due to two reasons: (1) Only one type of mass is known,
which leads to only one kind of gravitational force, which is attractive. The
many elementary particles that make up a large body, such as the earth, therefore exhibit an additive effect of their gravitational forces in line with the addition of their masses, which thus become very large. (2) The gravitational forces act over a large range, and decrease only as the square of the distance between two bodies.
By contrast, the electric charges of elementary particles, which give rise to
electrostatic and magnetic forces, are either positive or negative, or absent altogether. Only particles with opposite charges attract one another, and large
composite bodies therefore tend to be electrically neutral and inactive. On the
other hand, the nuclear forces, both strong and weak, are extremely short range
and become hardly noticeable at distances of the order of 1 million-millionth
of an inch.
Despite its macroscopic importance, the force of gravity remains so weak
that a body must be very massive before its influence is noticed by another.
Thus, the law of universal gravitation was deduced from observations of the
motions of the planets long before it could be checked experimentally. Not
until 1771 did the British physicist and chemist Henry Cavendish confirm it by
using large spheres of lead to attract small masses attached to a torsion pendulum, and from these measurements also deduced the density of the earth.
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In the two centuries after Newton, although mechanics was analyzed, reformulated, and applied to complex systems, no new physical ideas were added. The Swiss mathematician Leonhard Euler first formulated the equations of
motion for rigid bodies, while Newton had dealt only with masses concentrated at a point, which thus acted like particles. Various mathematical physicists,
among them Joseph Louis Lagrange of France and Sir William Rowan Hamilton of Ireland extended Newton's second law in more sophisticated and elegant
reformulations. Over the same period, Euler, the Dutch-born scientist Daniel
Bernoulli, and other scientists also extended Newtonian mechanics to lay the
foundation of fluid mechanics.
elucidation [ɪˌluːsɪ'deɪʃ(R)n ], [Rˌluːsɪ'deɪʃ(R)n] 1) консультирование, объяснение,
разъяснение 2) истолкование, трактовка, разъяснение 3) уяснение
interaction [ˌɪntRr'ækʃ(R)n] взаимодействие, взаимовлияние
close interaction between the vegetable and animal worlds — тесное взаимодей-
ствие растительного и животного мира
bind [baɪnd] bound вязать; связывать; завязывать
This problem is bound up with many others. — Эта проблема связана со многи-
ми другими.
cause [kɔːz] 1. причина, основание 2. 1) послужить причиной, поводом (для
чего-л.) ; мотивировать (что-л.) 2) заставлять; добиваться
to cause a thing to be done — заставить сделать что-л.; добиться выполнения
чего-л.
to cause smb. to be informed — поставить кого-л. в известность
Electricity and Magnetism
Although the ancient Greeks were aware of the electrostatic properties of
amber, and the Chinese as early as 2700 BC made crude magnets from lodestone, experimentation with and the understanding and use of electric and
magnetic phenomena did not occur until the end of the 18th century. In 1785
the French physicist Charles Augustin de Coulomb first confirmed experimentally that electrical charges attract or repel one another according to an inverse
square law, similar to that of gravitation. A powerful theory to calculate the
effect of any number of static electric charges arbitrarily distributed was sub-
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sequently developed by the French mathematician Siméon-Denis Poisson and
the German mathematician Carl Friedrich Gauss.
A positively charged particle attracts a negatively charged particle, tending
to accelerate one toward the other. If the medium through which the particle
moves offers resistance to that motion, this may be reduced to a constantvelocity (rather than accelerated) motion, and the medium will be heated up
and may also be otherwise affected. The ability to maintain an electromotive
force that could continue to drive electrically charged particles had to await the
development of the chemical battery by the Italian physicist Alessandro Volta
in 1800. The classical theory of a simple electric circuit assumes that the two
terminals of a battery are maintained positively and negatively charged as a
result of its internal properties. When the terminals are connected by a wire,
negatively charged particles will be simultaneously pushed away from the
negative terminal and attracted to the positive one, and in the process heat up
the wire that offers resistance to the motion. Upon their arrival at the positive
terminal, the battery will force the particles toward the negative terminal, overcoming the opposing forces of Coulomb's law. The German physicist Georg
Simon Ohm first discovered the existence of a simple proportionality constant
between the current flowing and the electromotive force supplied by a battery,
known as the resistance of the circuit. Ohm's law, which states that the resistance is equal to the electromotive force, or voltage, divided by the current,
is not a fundamental and universally applicable law of physics, but rather describes the behavior of a limited class of solid materials.
The historical concepts of magnetism, based on the existence of pairs of
oppositely charged poles, had started in the 17th century and owe much to the
work of Coulomb. The first connection between magnetism and electricity,
however, was made through the pioneering experiments of the Danish physicist and chemist Hans Christian Oersted, who in 1819 discovered that a magnetic needle could be deflected by a wire nearby carrying an electric current.
Within one week after learning of Oersted's discovery, the French scientist
André Marie Ampère showed experimentally that two current-carrying wires
would affect each other like poles of magnets. In 1831 the British physicist and
chemist Michael Faraday discovered that an electric current could be induced
(made to flow) in a wire without connection to a battery, either by moving a
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magnet or by placing another current-carrying wire with an unsteady — that is,
rising and falling — current nearby. The intimate connection between electricity and magnetism, now established, can best be stated in terms of electric or
magnetic fields, or forces that will act at a particular point on a unit charge or
unit current, respectively, placed at that point. Stationary electric charges produce electric fields; currents — that is, moving electric charges — produce
magnetic fields. Electric fields are also produced by changing magnetic fields,
and vice versa. Electric fields exert forces on charged particles as a function of
their charge alone; magnetic fields will exert an additional force only if the
charges are in motion.
These qualitative findings were finally put into a precise mathematical
form by the British physicist James Clerk Maxwell who, in developing the
partial differential equations that bear his name, related the space and time
changes of electric and magnetic fields at a point with the charge and current
densities at that point. In principle, they permit the calculation of the fields
everywhere and any time from a knowledge of the charges and currents. An
unexpected result arising from the solution of these equations was the prediction of a new kind of electromagnetic field, one that was produced by accelerating charges, that was propagated through space with the speed of light in the
form of an electromagnetic wave, and that decreased with the inverse square of
the distance from the source. In 1887 the German physicist Heinrich Rudolf
Hertz succeeded in actually generating such waves by electrical means, thereby laying the foundations for radio, radar, television, and other forms of telecommunications.
The behavior of electric and magnetic fields in these waves is quite similar
to that of a very long taut string, one end of which is rapidly moved up and
down in a periodic fashion. Any point along the string will be observed to
move up and down, or oscillate, with the same period or with the same frequency as the source. Points along the string at different distances from the
source will reach the maximum vertical displacements at different times, or at
a different phase. Each point along the string will do what its neighbor did, but
a little later, if it is further removed from the vibrating source. The speed with
which the disturbance, or the message to oscillate, is transmitted along the
string is called the wave velocity. This is a function of the medium, its mass,
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and the tension in the case of a string. An instantaneous snapshot of the string
(after it has been in motion for a while) would show equispaced points having
the same displacement and motion, separated by a distance known as the
wavelength, which is equal to the wave velocity divided by the frequency. In
the case of the electromagnetic field one can think of the electric-field strength
as taking the place of the up-and-down motion of each piece of the string, with
the magnetic field acting similarly at a direction at right angles to that of the
electric field. The electromagnetic-wave velocity away from the source is the
speed of light.
aware [R'wɛR] знающий, осведомлённый, сведущи й , созн ающ ий
keenly / painfully / very much aware — хорошо осведомлённый, в высшей сте-
пени компетентный
to be aware of / that — знать, сознавать, отдавать себе полный отчёт
They were aware of the difficulties. — Они знали о трудностях.
He was aware that the deadline had passed. — Ему было известно, что срок прошёл.
He is aware of danger. — Он сознаёт грозящую опасность.
crude [kruːd] 1) необработанный, неочищенный; необожжённый (о кирпиче)
2) незрелый, неспелый (о плодах) 3) несовершенный, примитивный
attract [R'trækt] 1) притягивать 2) привлекать, притягивать (внимание, инве-
стиции)
Anything with strong gravity attracts other things to it. — Любое тело с большой
массой притягивает к себе другие.
He shouted to attract attention. — Он закричал, чтобы обратить на себя внимание.
A crowd was attracted to the scene of the accident. — Толпа была привлечена на
место происшествия.
arbitrarily [ˌɑːbɪ'tre(R)r(R)lɪ ], ['ɑːbɪtr(R)r(R)lɪ] без достаточных оснований, произвольно; своевольно
resistance [rɪ'zɪst(R)n(t)s] стойкость, ак тивно е сопротивление, активная составляющая импеданса, устойчивость (к воздействиям)
await [R'weɪt] дожидаться, ждать, ожидать, поджидать
assume [R'sjuːm] 1) принимать, брать на себя (ответственность, управление)
2) принимать, обретать (характер, форму) 3) притворяться, прикидываться
to assume responsibility – брать на себя, признавать ответственность
to assume control – взять на себя управление (чем-л.)
to assume measures – принимать меры
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to assume office – вступать в должность
Mr. These Doctrines assume at once a reasonableness and an importance. — Эти
учения сразу приобретают обоснованный и значительный вид. She assumed an air
of confidence in spite of her dismay. — Она напустила на себя уверенный вид, хотя
была в смятении.
simultaneously [ˌsɪm(R)l'teɪnɪRslɪ] 1) одн ов ре м ен н о 2) попутно 3) совместно
solve equations simultaneously — решать уравнение совместно
offer ['ɔfR] 1. 1) предлагать 2) выдвигать, предлагать вниманию
to offer help — предложить помощь
to offer information / advice — предоставить информацию / совет
He offered to help me. — Он предложил мне свою помощь.
We have been successful because we are offering a quality service. — Мы доби-
лись успеха, потому что предлагаем качественное обслуживание.
They offered us many solutions to a problem. — Они предложили нашему вни-
манию много решений данной проблемы.
discovered [dɪ'skʌvRd] выявленный, обнаруженный; разоблаченный, обнаро-
дованный
owe [Ru] 1) быть должным (кому-л.); быть в долгу (перед кем-л.) 2) приписы-
вать (успех, открытие)
The company owes its success to its excellent training programme. — Компания
приписывает свой успех отличной программе тренингов, которую проводит.
We owe this idea to Greek philosophy. — Эту идею мы унаследовали от греческой философии.
deflected [dɪ'flektɪd] отклонённый, согнутый, отогнутый, изогнутый; искрив-
лённый
affect [R'fekt] 1) оказывать воздействие, влияние; касаться, затрагивать. 2)
волновать, трогать (эмоционально) 3) приносить вред, наносить ущерб
shouting affects the voice — громкий крик вредит голосу
to affect smb. deeply — сильно повлиять на кого-л
induce [ɪn'djuːs] 1) побуж д ать, склонять, 2) вызывать; стимулировать; приво-
дить (к чему-л.) 3) выводить умозаключени е (путём индукции)
From a sufficient number of results a proposition or law is induced. — Исходя из
достаточного количества результатов можно сделать вывод или установить закономерность.
unsteady [ʌn'stedɪ] 1) неустойчивы й ; нетвёрдый, ш а тк и й 2) нерегулярн ы й , неравномерный, нестабильный 3) неустойчивый, нестабильный (о рынке, ценах,
курсах)
unsteady handwriting — неровный почерк an
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